Invitation: celebrating 50 years of OEIS, 250000 sequences, and Sloane's 75th, there will be a conference at DIMACS, Rutgers, Oct 9-10 2014.
0,3
The number of n-node binary trees fixed by the corresponding automorphism(s).
Table of n, a(n) for n=0..20.
A. Karttunen, C-program for computing the initial terms of this sequence
Sequence in context: A180019 A112801 A173862 * A096323 A035682 A054543
Adjacent sequences: A089870 A089871 A089872 * A089874 A089875 A089876
nonn
Antti Karttunen, Nov 29 2003
approved